He told Collider that the eradiction of all forms of death will lead to a global crisis in the new ten-part run, subtitled Miracle Day.

"The possibility of death ceases to exist," he explained. "That's great news for some people, but globally it becomes a problem. That's what the whole [series] is about. It's an instant overnight population boom where, suddenly, the Earth relies on people dying."

He added: "Suddenly you've got a crisis affecting everyone on the planet. That's where the Torchwood team and our brand new characters come in."

Discussing the new cast members, Davies claimed that the decision to kill off regular characters in the past has helped to keep the show fresh.

"A lot of more straightforward science fiction shows on big networks get a cast of 12, and they are all under contract for seven years, so they all stay with you for seven years," he suggested. "Torchwood was always at a high body count because I think it makes the story stronger and more dangerous and more frightening.

"You cannot guarantee who will survive, and I think that raises the stakes for everyone."

Torchwood: Miracle Day will air on BBC One in the UK and Starz in the US.